Looking Back at the I-35W Bridge Collapse – Now Known as “America’s Wake-Up Call”

The Day the I-35W Bridge Fell

August 1, 2007, was one of the most devastating days in Minneapolis’s history. It was the day when the I-35W, aka Bridge 9340, suddenly collapsed during rush hour and sent vehicles plunging into the Mississippi River. The catastrophe killed 13 people, injured 145 others, and exposed serious infrastructure problems across America.

The catastrophe killed 13 people, injured 145 others, and exposed serious infrastructure problems across America.

There Were Warning Signs Already

The federal government rated the bridge ‘structurally deficient’ twice: in 1990 and 2005. The 2005 report also mentioned it was ‘in possible need of replacement.’

On June 15, 2006, inspections discovered signs of infrastructure fatigue and cracking. The day after the collapse, then-governor Tim Pawlenty announced that the I-35W was actually scheduled for replacement in 2020.

The Collapse Happened in Seconds

At 6:05 PM, cameras show over 1,000 feet of the bridge, which included 456 feet of the main span. 11 vehicles, including a school bus full of children, fell 108 feet into the river. Some landed on the riverbank, while others fell into 15-foot deep water.

This included the construction crew working on the bridge at that time. In all, the bridge collapse claimed 13 lives and injured 145 others.

Emergency Responders Arrived Quickly

Emergency crews arrived within minutes of the I-35W collapse. The fire department sent boats for water rescues, with the first teams arriving just six minutes after the collapse.

Navy divers helped search the murky river where they could only see 6-8 inches ahead. Over 75 agencies helped, including 22 fire departments and 31 police departments.

In all, it only took around 81 minutes to get 145 patients to nearby hospitals with the help of paramedics.

Terrible Design Caused the Collapse

After a 16-month study, experts found that the steel connector plates were too thin—only 1/2 inch instead of the needed 1 inch.

The extra weight from construction materials combined with this design flaw caused the bridge to fail. Engineers from Sverdrup & Parcel made math errors when designing the bridge in 1964, and no one caught these mistakes during the bridge’s 39-year life.

The New I-35W Was Built in Less Than a Year

Work on the replacement bridge, renamed the I-35W Saint Anthony Falls Bridge, began just three months after the collapse.

Amazingly, it was finished in only 11 months—three months early—and opened on September 18, 2008. Workers built around the clock, with the construction companies getting $200,000 for each day they finished early.

In 2009, the Design-Build Institute of America awarded the ‘Best Overall Design-Build Project Award’ to the new bridge.

The New Bridge Has Advanced Monitoring Systems

The new bridge has 323 sensors that constantly check its health, measuring stress and rust. It also has spray nozzles that prevent ice during Minnesota’s harsh winters, when temperatures often drop below -20°F.

The design is completely different from the old bridge, using modern building methods to make it safer and stronger than the original.

Victims Received Financial Settlements

Minnesota created a special fund that paid $37 million to victims and families, with payments up to $400,000 each.

Additional lawsuits against the engineering firm URS Corporation and Progressive Contractors settled for $52.4 million.

The state had to change a law that limited payments to $1 million per incident. Garrett Ebling, who had many broken bones and was in a coma, received the largest payment of $4.3 million.

The Collapse Polluted the River

The collapse stirred up years of pollution in the river, releasing harmful chemicals that had collected since the 1940s.

Teams worked to contain leaks from the 50+ underwater vehicles, including 10,000 gallons of gas and oil and 1,200 gallons of antifreeze.

Special equipment absorbed oil and monitored water quality. Testing continued until 2012, showing mercury levels still 3.8 times higher than normal five years after the collapse.

Thousands of Bridges Were Checked After

After the collapse, 18,000 similar bridges across America were checked, with 1,150 needing immediate fixes.

The government gave an extra $1 billion specifically for bridge repairs. New rules now require engineers to check the strength of connector plates, something that was previously overlooked.

Engineers must take special training on how to inspect these critical parts, with required certification programs starting in 2010.

It Became “America’s Wake-Up Call”

The collapse was also called ‘America’s wake-up call’ about failing infrastructure. About 47,000 bridges (8% of all bridges) had similar problems.

The American Society of Civil Engineers gave America’s bridges a C grade, saying $2.2 trillion was needed for fixes.

The disaster changed public opinion—a 2008 poll showed 71% of Americans supported more infrastructure spending, up from 46% before the collapse.